PLT-3753 Added Segment analytics (#3972)

29 files changed, 2390 insertions, 0 deletions

diff --git a/vendor/github.com/jehiah/go-strftime/README.md b/vendor/github.com/jehiah/go-strftime/README.md
new file mode 100644
index 000000000..8eb240384
--- /dev/null
+++ b/vendor/github.com/jehiah/go-strftime/README.md
@@ -0,0 +1,4 @@
+go-strftime
+===========
+
+go implementation of strftime
\ No newline at end of file
diff --git a/vendor/github.com/jehiah/go-strftime/strftime.go b/vendor/github.com/jehiah/go-strftime/strftime.go
new file mode 100644
index 000000000..99e26716f
--- /dev/null
+++ b/vendor/github.com/jehiah/go-strftime/strftime.go
@@ -0,0 +1,71 @@
+// go implementation of strftime
+package strftime
+
+import (
+	"strings"
+	"time"
+)
+
+// taken from time/format.go
+var conversion = map[rune]string {
+	/*stdLongMonth      */ 'B':"January",
+	/*stdMonth          */ 'b': "Jan",
+	// stdNumMonth       */ 'm': "1",
+	/*stdZeroMonth      */ 'm': "01",
+	/*stdLongWeekDay    */ 'A': "Monday",
+	/*stdWeekDay        */ 'a': "Mon",
+	// stdDay            */ 'd': "2",
+	// stdUnderDay       */ 'd': "_2",
+	/*stdZeroDay        */ 'd': "02",
+	/*stdHour           */ 'H': "15",
+	// stdHour12         */ 'I': "3",
+	/*stdZeroHour12     */ 'I': "03",
+	// stdMinute         */ 'M': "4",
+	/*stdZeroMinute     */ 'M': "04",
+	// stdSecond         */ 'S': "5",
+	/*stdZeroSecond     */ 'S': "05",
+	/*stdLongYear       */ 'Y': "2006",
+	/*stdYear           */ 'y': "06",
+	/*stdPM             */ 'p': "PM",
+	// stdpm             */ 'p': "pm",
+	/*stdTZ             */ 'Z': "MST",
+	// stdISO8601TZ      */ 'z': "Z0700",  // prints Z for UTC
+	// stdISO8601ColonTZ */ 'z': "Z07:00", // prints Z for UTC
+	/*stdNumTZ          */ 'z': "-0700",  // always numeric
+	// stdNumShortTZ     */ 'b': "-07",    // always numeric
+	// stdNumColonTZ     */ 'b': "-07:00", // always numeric
+}
+
+// This is an alternative to time.Format because no one knows 
+// what date 040305 is supposed to create when used as a 'layout' string
+// this takes standard strftime format options. For a complete list
+// of format options see http://strftime.org/
+func Format(format string, t time.Time) string {
+	retval := make([]byte, 0, len(format))
+	for i, ni := 0, 0; i < len(format); i = ni + 2 {
+		ni = strings.IndexByte(format[i:], '%')
+		if ni < 0 {
+			ni = len(format)
+		} else {
+			ni += i
+		}
+		retval = append(retval, []byte(format[i:ni])...)
+		if ni + 1 < len(format) {
+			c := format[ni + 1]
+			if c == '%' {
+				retval = append(retval, '%')
+			} else {
+				if layoutCmd, ok := conversion[rune(c)]; ok {
+					retval = append(retval, []byte(t.Format(layoutCmd))...)
+				} else {
+					retval = append(retval, '%', c)
+				}
+			}
+		} else {
+			if ni < len(format) {
+				retval = append(retval, '%')
+			}
+		}
+	}
+	return string(retval)
+}
diff --git a/vendor/github.com/jehiah/go-strftime/strftime_test.go b/vendor/github.com/jehiah/go-strftime/strftime_test.go
new file mode 100644
index 000000000..45cbca345
--- /dev/null
+++ b/vendor/github.com/jehiah/go-strftime/strftime_test.go
@@ -0,0 +1,40 @@
+package strftime
+
+import (
+	"time"
+	"fmt"
+	"testing"
+)
+
+func ExampleFormat() {
+	t := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	t = t.In(utc)
+	fmt.Println(Format("%Y-%m-%d %H:%M:%S", t))
+	// Output:
+	// 2012-06-21 02:12:56
+}
+
+func TestNoLeadingPercentSign(t *testing.T) {
+	tm := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	tm = tm.In(utc)
+	result := Format("aaabbb0123456789%Y", tm)
+	if result != "aaabbb01234567892012" {
+		t.Logf("%s != %s", result, "aaabbb01234567892012")
+		t.Fail()
+	}
+}
+
+
+func TestUnsupported(t *testing.T) {
+	tm := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	tm = tm.In(utc)
+	result := Format("%0%1%%%2", tm)
+	if result != "%0%1%%2" {
+		t.Logf("%s != %s", result, "%0%1%%2")
+		t.Fail()
+	}
+}
+
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/Godeps.json b/vendor/github.com/segmentio/analytics-go/Godeps/Godeps.json
new file mode 100644
index 000000000..e1b79eb2d
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/Godeps.json
@@ -0,0 +1,17 @@
+{
+	"ImportPath": "github.com/segmentio/analytics-go",
+	"GoVersion": "go1.4.2",
+	"Packages": [
+		"./..."
+	],
+	"Deps": [
+		{
+			"ImportPath": "github.com/jehiah/go-strftime",
+			"Rev": "834e15c05a45371503440cc195bbd05c9a0968d9"
+		},
+		{
+			"ImportPath": "github.com/xtgo/uuid",
+			"Rev": "a0b114877d4caeffbd7f87e3757c17fce570fea7"
+		}
+	]
+}
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/Readme b/vendor/github.com/segmentio/analytics-go/Godeps/Readme
new file mode 100644
index 000000000..4cdaa53d5
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/Readme
@@ -0,0 +1,5 @@
+This directory tree is generated automatically by godep.
+
+Please do not edit.
+
+See https://github.com/tools/godep for more information.
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/.gitignore b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/.gitignore
new file mode 100644
index 000000000..f037d684e
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/.gitignore
@@ -0,0 +1,2 @@
+/pkg
+/bin
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/.gitignore b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/.gitignore
new file mode 100644
index 000000000..00268614f
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/.gitignore
@@ -0,0 +1,22 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/README.md b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/README.md
new file mode 100644
index 000000000..8eb240384
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/README.md
@@ -0,0 +1,4 @@
+go-strftime
+===========
+
+go implementation of strftime
\ No newline at end of file
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime.go b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime.go
new file mode 100644
index 000000000..99e26716f
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime.go
@@ -0,0 +1,71 @@
+// go implementation of strftime
+package strftime
+
+import (
+	"strings"
+	"time"
+)
+
+// taken from time/format.go
+var conversion = map[rune]string {
+	/*stdLongMonth      */ 'B':"January",
+	/*stdMonth          */ 'b': "Jan",
+	// stdNumMonth       */ 'm': "1",
+	/*stdZeroMonth      */ 'm': "01",
+	/*stdLongWeekDay    */ 'A': "Monday",
+	/*stdWeekDay        */ 'a': "Mon",
+	// stdDay            */ 'd': "2",
+	// stdUnderDay       */ 'd': "_2",
+	/*stdZeroDay        */ 'd': "02",
+	/*stdHour           */ 'H': "15",
+	// stdHour12         */ 'I': "3",
+	/*stdZeroHour12     */ 'I': "03",
+	// stdMinute         */ 'M': "4",
+	/*stdZeroMinute     */ 'M': "04",
+	// stdSecond         */ 'S': "5",
+	/*stdZeroSecond     */ 'S': "05",
+	/*stdLongYear       */ 'Y': "2006",
+	/*stdYear           */ 'y': "06",
+	/*stdPM             */ 'p': "PM",
+	// stdpm             */ 'p': "pm",
+	/*stdTZ             */ 'Z': "MST",
+	// stdISO8601TZ      */ 'z': "Z0700",  // prints Z for UTC
+	// stdISO8601ColonTZ */ 'z': "Z07:00", // prints Z for UTC
+	/*stdNumTZ          */ 'z': "-0700",  // always numeric
+	// stdNumShortTZ     */ 'b': "-07",    // always numeric
+	// stdNumColonTZ     */ 'b': "-07:00", // always numeric
+}
+
+// This is an alternative to time.Format because no one knows 
+// what date 040305 is supposed to create when used as a 'layout' string
+// this takes standard strftime format options. For a complete list
+// of format options see http://strftime.org/
+func Format(format string, t time.Time) string {
+	retval := make([]byte, 0, len(format))
+	for i, ni := 0, 0; i < len(format); i = ni + 2 {
+		ni = strings.IndexByte(format[i:], '%')
+		if ni < 0 {
+			ni = len(format)
+		} else {
+			ni += i
+		}
+		retval = append(retval, []byte(format[i:ni])...)
+		if ni + 1 < len(format) {
+			c := format[ni + 1]
+			if c == '%' {
+				retval = append(retval, '%')
+			} else {
+				if layoutCmd, ok := conversion[rune(c)]; ok {
+					retval = append(retval, []byte(t.Format(layoutCmd))...)
+				} else {
+					retval = append(retval, '%', c)
+				}
+			}
+		} else {
+			if ni < len(format) {
+				retval = append(retval, '%')
+			}
+		}
+	}
+	return string(retval)
+}
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime_test.go b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime_test.go
new file mode 100644
index 000000000..45cbca345
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/jehiah/go-strftime/strftime_test.go
@@ -0,0 +1,40 @@
+package strftime
+
+import (
+	"time"
+	"fmt"
+	"testing"
+)
+
+func ExampleFormat() {
+	t := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	t = t.In(utc)
+	fmt.Println(Format("%Y-%m-%d %H:%M:%S", t))
+	// Output:
+	// 2012-06-21 02:12:56
+}
+
+func TestNoLeadingPercentSign(t *testing.T) {
+	tm := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	tm = tm.In(utc)
+	result := Format("aaabbb0123456789%Y", tm)
+	if result != "aaabbb01234567892012" {
+		t.Logf("%s != %s", result, "aaabbb01234567892012")
+		t.Fail()
+	}
+}
+
+
+func TestUnsupported(t *testing.T) {
+	tm := time.Unix(1340244776, 0)
+	utc, _ := time.LoadLocation("UTC")
+	tm = tm.In(utc)
+	result := Format("%0%1%%%2", tm)
+	if result != "%0%1%%2" {
+		t.Logf("%s != %s", result, "%0%1%%2")
+		t.Fail()
+	}
+}
+
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/AUTHORS b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/AUTHORS
new file mode 100644
index 000000000..a6f045160
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/AUTHORS
@@ -0,0 +1,5 @@
+# This source file refers to The gocql Authors for copyright purposes.
+
+Christoph Hack <christoph@tux21b.org>
+Jonathan Rudenberg <jonathan@titanous.com>
+Thorsten von Eicken <tve@rightscale.com>
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/LICENSE b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/LICENSE
new file mode 100644
index 000000000..18d25f923
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2012 The gocql Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid.go b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid.go
new file mode 100644
index 000000000..a0fd7a5a5
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid.go
@@ -0,0 +1,204 @@
+// Copyright (c) 2012 The gocql Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package uuid can be used to generate and parse universally unique
+// identifiers, a standardized format in the form of a 128 bit number.
+//
+// http://tools.ietf.org/html/rfc4122
+package uuid
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"errors"
+	"io"
+	"net"
+	"strconv"
+	"time"
+)
+
+type UUID [16]byte
+
+var hardwareAddr []byte
+
+const (
+	VariantNCSCompat = 0
+	VariantIETF      = 2
+	VariantMicrosoft = 6
+	VariantFuture    = 7
+)
+
+func init() {
+	if interfaces, err := net.Interfaces(); err == nil {
+		for _, i := range interfaces {
+			if i.Flags&net.FlagLoopback == 0 && len(i.HardwareAddr) > 0 {
+				hardwareAddr = i.HardwareAddr
+				break
+			}
+		}
+	}
+	if hardwareAddr == nil {
+		// If we failed to obtain the MAC address of the current computer,
+		// we will use a randomly generated 6 byte sequence instead and set
+		// the multicast bit as recommended in RFC 4122.
+		hardwareAddr = make([]byte, 6)
+		_, err := io.ReadFull(rand.Reader, hardwareAddr)
+		if err != nil {
+			panic(err)
+		}
+		hardwareAddr[0] = hardwareAddr[0] | 0x01
+	}
+}
+
+// Parse parses a 32 digit hexadecimal number (that might contain hyphens)
+// representing an UUID.
+func Parse(input string) (UUID, error) {
+	var u UUID
+	j := 0
+	for i := 0; i < len(input); i++ {
+		b := input[i]
+		switch {
+		default:
+			fallthrough
+		case j == 32:
+			goto err
+		case b == '-':
+			continue
+		case '0' <= b && b <= '9':
+			b -= '0'
+		case 'a' <= b && b <= 'f':
+			b -= 'a' - 10
+		case 'A' <= b && b <= 'F':
+			b -= 'A' - 10
+		}
+		u[j/2] |= b << byte(^j&1<<2)
+		j++
+	}
+	if j == 32 {
+		return u, nil
+	}
+err:
+	return UUID{}, errors.New("invalid UUID " + strconv.Quote(input))
+}
+
+// FromBytes converts a raw byte slice to an UUID. It will panic if the slice
+// isn't exactly 16 bytes long.
+func FromBytes(input []byte) UUID {
+	var u UUID
+	if len(input) != 16 {
+		panic("UUIDs must be exactly 16 bytes long")
+	}
+	copy(u[:], input)
+	return u
+}
+
+// NewRandom generates a totally random UUID (version 4) as described in
+// RFC 4122.
+func NewRandom() UUID {
+	var u UUID
+	io.ReadFull(rand.Reader, u[:])
+	u[6] &= 0x0F // clear version
+	u[6] |= 0x40 // set version to 4 (random uuid)
+	u[8] &= 0x3F // clear variant
+	u[8] |= 0x80 // set to IETF variant
+	return u
+}
+
+var timeBase = time.Date(1582, time.October, 15, 0, 0, 0, 0, time.UTC).Unix()
+
+// NewTime generates a new time based UUID (version 1) as described in RFC
+// 4122. This UUID contains the MAC address of the node that generated the
+// UUID, a timestamp and a sequence number.
+func NewTime() UUID {
+	var u UUID
+
+	now := time.Now().In(time.UTC)
+	t := uint64(now.Unix()-timeBase)*10000000 + uint64(now.Nanosecond()/100)
+	u[0], u[1], u[2], u[3] = byte(t>>24), byte(t>>16), byte(t>>8), byte(t)
+	u[4], u[5] = byte(t>>40), byte(t>>32)
+	u[6], u[7] = byte(t>>56)&0x0F, byte(t>>48)
+
+	var clockSeq [2]byte
+	io.ReadFull(rand.Reader, clockSeq[:])
+	u[8] = clockSeq[1]
+	u[9] = clockSeq[0]
+
+	copy(u[10:], hardwareAddr)
+
+	u[6] |= 0x10 // set version to 1 (time based uuid)
+	u[8] &= 0x3F // clear variant
+	u[8] |= 0x80 // set to IETF variant
+
+	return u
+}
+
+// String returns the UUID in it's canonical form, a 32 digit hexadecimal
+// number in the form of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
+func (u UUID) String() string {
+	buf := [36]byte{8: '-', 13: '-', 18: '-', 23: '-'}
+	hex.Encode(buf[0:], u[0:4])
+	hex.Encode(buf[9:], u[4:6])
+	hex.Encode(buf[14:], u[6:8])
+	hex.Encode(buf[19:], u[8:10])
+	hex.Encode(buf[24:], u[10:])
+	return string(buf[:])
+}
+
+// Bytes returns the raw byte slice for this UUID. A UUID is always 128 bits
+// (16 bytes) long.
+func (u UUID) Bytes() []byte {
+	return u[:]
+}
+
+// Variant returns the variant of this UUID. This package will only generate
+// UUIDs in the IETF variant.
+func (u UUID) Variant() int {
+	x := u[8]
+	switch byte(0) {
+	case x & 0x80:
+		return VariantNCSCompat
+	case x & 0x40:
+		return VariantIETF
+	case x & 0x20:
+		return VariantMicrosoft
+	}
+	return VariantFuture
+}
+
+// Version extracts the version of this UUID variant. The RFC 4122 describes
+// five kinds of UUIDs.
+func (u UUID) Version() int {
+	return int(u[6] & 0xF0 >> 4)
+}
+
+// Node extracts the MAC address of the node who generated this UUID. It will
+// return nil if the UUID is not a time based UUID (version 1).
+func (u UUID) Node() []byte {
+	if u.Version() != 1 {
+		return nil
+	}
+	return u[10:]
+}
+
+// Timestamp extracts the timestamp information from a time based UUID
+// (version 1).
+func (u UUID) Timestamp() uint64 {
+	if u.Version() != 1 {
+		return 0
+	}
+	return uint64(u[0])<<24 + uint64(u[1])<<16 + uint64(u[2])<<8 +
+		uint64(u[3]) + uint64(u[4])<<40 + uint64(u[5])<<32 +
+		uint64(u[7])<<48 + uint64(u[6]&0x0F)<<56
+}
+
+// Time is like Timestamp, except that it returns a time.Time.
+func (u UUID) Time() time.Time {
+	t := u.Timestamp()
+	if t == 0 {
+		return time.Time{}
+	}
+	sec := t / 10000000
+	nsec := t - sec
+	return time.Unix(int64(sec)+timeBase, int64(nsec))
+}
diff --git a/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid_test.go b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid_test.go
new file mode 100644
index 000000000..3cef4a31a
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Godeps/_workspace/src/github.com/xtgo/uuid/uuid_test.go
@@ -0,0 +1,102 @@
+// Copyright (c) 2012 The gocql Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package uuid
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestNil(t *testing.T) {
+	var uuid UUID
+	want, got := "00000000-0000-0000-0000-000000000000", uuid.String()
+	if want != got {
+		t.Fatalf("TestNil: expected %q got %q", want, got)
+	}
+}
+
+var tests = []struct {
+	input   string
+	variant int
+	version int
+}{
+	{"b4f00409-cef8-4822-802c-deb20704c365", VariantIETF, 4},
+	{"f81d4fae-7dec-11d0-a765-00a0c91e6bf6", VariantIETF, 1},
+	{"00000000-7dec-11d0-a765-00a0c91e6bf6", VariantIETF, 1},
+	{"3051a8d7-aea7-1801-e0bf-bc539dd60cf3", VariantFuture, 1},
+	{"3051a8d7-aea7-2801-e0bf-bc539dd60cf3", VariantFuture, 2},
+	{"3051a8d7-aea7-3801-e0bf-bc539dd60cf3", VariantFuture, 3},
+	{"3051a8d7-aea7-4801-e0bf-bc539dd60cf3", VariantFuture, 4},
+	{"3051a8d7-aea7-3801-e0bf-bc539dd60cf3", VariantFuture, 5},
+	{"d0e817e1-e4b1-1801-3fe6-b4b60ccecf9d", VariantNCSCompat, 0},
+	{"d0e817e1-e4b1-1801-bfe6-b4b60ccecf9d", VariantIETF, 1},
+	{"d0e817e1-e4b1-1801-dfe6-b4b60ccecf9d", VariantMicrosoft, 0},
+	{"d0e817e1-e4b1-1801-ffe6-b4b60ccecf9d", VariantFuture, 0},
+}
+
+func TestPredefined(t *testing.T) {
+	for i := range tests {
+		uuid, err := Parse(tests[i].input)
+		if err != nil {
+			t.Errorf("Parse #%d: %v", i, err)
+			continue
+		}
+
+		if str := uuid.String(); str != tests[i].input {
+			t.Errorf("String #%d: expected %q got %q", i, tests[i].input, str)
+			continue
+		}
+
+		if variant := uuid.Variant(); variant != tests[i].variant {
+			t.Errorf("Variant #%d: expected %d got %d", i, tests[i].variant, variant)
+		}
+
+		if tests[i].variant == VariantIETF {
+			if version := uuid.Version(); version != tests[i].version {
+				t.Errorf("Version #%d: expected %d got %d", i, tests[i].version, version)
+			}
+		}
+	}
+}
+
+func TestNewRandom(t *testing.T) {
+	for i := 0; i < 20; i++ {
+		uuid := NewRandom()
+
+		if variant := uuid.Variant(); variant != VariantIETF {
+			t.Errorf("wrong variant. expected %d got %d", VariantIETF, variant)
+		}
+		if version := uuid.Version(); version != 4 {
+			t.Errorf("wrong version. expected %d got %d", 4, version)
+		}
+	}
+}
+
+func TestNewTime(t *testing.T) {
+	var node []byte
+	timestamp := uint64(0)
+	for i := 0; i < 20; i++ {
+		uuid := NewTime()
+
+		if variant := uuid.Variant(); variant != VariantIETF {
+			t.Errorf("wrong variant. expected %d got %d", VariantIETF, variant)
+		}
+		if version := uuid.Version(); version != 1 {
+			t.Errorf("wrong version. expected %d got %d", 1, version)
+		}
+
+		if n := uuid.Node(); !bytes.Equal(n, node) && i > 0 {
+			t.Errorf("wrong node. expected %x, got %x", node, n)
+		} else if i == 0 {
+			node = n
+		}
+
+		ts := uuid.Timestamp()
+		if ts < timestamp {
+			t.Errorf("timestamps must grow")
+		}
+		timestamp = ts
+	}
+}
diff --git a/vendor/github.com/segmentio/analytics-go/History.md b/vendor/github.com/segmentio/analytics-go/History.md
new file mode 100644
index 000000000..e8538a0cc
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/History.md
@@ -0,0 +1,67 @@
+
+v2.1.1 / 2016-04-26
+===================
+
+ * Fix blocking the goroutine when Close is the first call.
+ * Fix blocking the goroutine when the message queue fills up.
+
+v2.1.0 / 2015-12-28
+===================
+
+ * Add ability to set custom timestamps for messages.
+ * Add ability to set a custom `net/http` client.
+ * Add ability to set a custom logger.
+ * Fix edge case when client would try to upload no messages.
+ * Properly upload in-flight messages when client is asked to shutdown.
+ * Add ability to set `.integrations` field on messages.
+ * Fix resource leak with interval ticker after shutdown.
+ * Add retries and back-off when uploading messages.
+ * Add ability to set  custom flush interval.
+
+v2.0.0 / 2015-02-03
+===================
+
+ * rewrite with breaking API changes
+
+v1.2.0 / 2014-09-03
+==================
+
+ * add public .Flush() method
+ * rename .Stop() to .Close()
+
+v1.1.0 / 2014-09-02
+==================
+
+ * add client.Stop() to flash/wait. Closes #7
+
+v1.0.0 / 2014-08-26
+==================
+
+ * fix response close
+ * change comments to be more go-like
+ * change uuid libraries
+
+0.1.2 / 2014-06-11
+==================
+
+ * add runnable example
+ * fix: close body
+
+0.1.1 / 2014-05-31
+==================
+
+ * refactor locking
+
+0.1.0 / 2014-05-22
+==================
+
+ * replace Debug option with debug package
+
+0.0.2 / 2014-05-20
+==================
+
+ * add .Start()
+ * add mutexes
+ * rename BufferSize to FlushAt and FlushInterval to FlushAfter
+ * lower FlushInterval to 5 seconds
+ * lower BufferSize to 20 to match other clients
diff --git a/vendor/github.com/segmentio/analytics-go/Makefile b/vendor/github.com/segmentio/analytics-go/Makefile
new file mode 100644
index 000000000..e896b1b5f
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Makefile
@@ -0,0 +1,10 @@
+vet:
+	@godep go vet ./...
+
+build:
+	@godep go build
+
+test:
+	@godep go test -race -cover ./...
+
+.PHONY: vet build test
diff --git a/vendor/github.com/segmentio/analytics-go/Readme.md b/vendor/github.com/segmentio/analytics-go/Readme.md
new file mode 100644
index 000000000..b521cbe63
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/Readme.md
@@ -0,0 +1,8 @@
+# analytics-go
+
+  Segment analytics client for Go. For additional documentation
+  visit [https://segment.com/docs/libraries/go](https://segment.com/docs/libraries/go/) or view the [godocs](http://godoc.org/github.com/segmentio/analytics-go).
+
+## License
+
+ MIT
diff --git a/vendor/github.com/segmentio/analytics-go/analytics.go b/vendor/github.com/segmentio/analytics-go/analytics.go
new file mode 100644
index 000000000..6ec93fcbf
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/analytics.go
@@ -0,0 +1,407 @@
+package analytics
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"sync"
+
+	"bytes"
+	"encoding/json"
+	"errors"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/jehiah/go-strftime"
+	"github.com/segmentio/backo-go"
+	"github.com/xtgo/uuid"
+)
+
+// Version of the client.
+const Version = "2.1.0"
+
+// Endpoint for the Segment API.
+const Endpoint = "https://api.segment.io"
+
+// DefaultContext of message batches.
+var DefaultContext = map[string]interface{}{
+	"library": map[string]interface{}{
+		"name":    "analytics-go",
+		"version": Version,
+	},
+}
+
+// Backoff policy.
+var Backo = backo.DefaultBacko()
+
+// Message interface.
+type message interface {
+	setMessageId(string)
+	setTimestamp(string)
+}
+
+// Message fields common to all.
+type Message struct {
+	Type      string `json:"type,omitempty"`
+	MessageId string `json:"messageId,omitempty"`
+	Timestamp string `json:"timestamp,omitempty"`
+	SentAt    string `json:"sentAt,omitempty"`
+}
+
+// Batch message.
+type Batch struct {
+	Context  map[string]interface{} `json:"context,omitempty"`
+	Messages []interface{}          `json:"batch"`
+	Message
+}
+
+// Identify message.
+type Identify struct {
+	Context      map[string]interface{} `json:"context,omitempty"`
+	Integrations map[string]interface{} `json:"integrations,omitempty"`
+	Traits       map[string]interface{} `json:"traits,omitempty"`
+	AnonymousId  string                 `json:"anonymousId,omitempty"`
+	UserId       string                 `json:"userId,omitempty"`
+	Message
+}
+
+// Group message.
+type Group struct {
+	Context      map[string]interface{} `json:"context,omitempty"`
+	Integrations map[string]interface{} `json:"integrations,omitempty"`
+	Traits       map[string]interface{} `json:"traits,omitempty"`
+	AnonymousId  string                 `json:"anonymousId,omitempty"`
+	UserId       string                 `json:"userId,omitempty"`
+	GroupId      string                 `json:"groupId"`
+	Message
+}
+
+// Track message.
+type Track struct {
+	Context      map[string]interface{} `json:"context,omitempty"`
+	Integrations map[string]interface{} `json:"integrations,omitempty"`
+	Properties   map[string]interface{} `json:"properties,omitempty"`
+	AnonymousId  string                 `json:"anonymousId,omitempty"`
+	UserId       string                 `json:"userId,omitempty"`
+	Event        string                 `json:"event"`
+	Message
+}
+
+// Page message.
+type Page struct {
+	Context      map[string]interface{} `json:"context,omitempty"`
+	Integrations map[string]interface{} `json:"integrations,omitempty"`
+	Traits       map[string]interface{} `json:"properties,omitempty"`
+	AnonymousId  string                 `json:"anonymousId,omitempty"`
+	UserId       string                 `json:"userId,omitempty"`
+	Category     string                 `json:"category,omitempty"`
+	Name         string                 `json:"name,omitempty"`
+	Message
+}
+
+// Alias message.
+type Alias struct {
+	PreviousId string `json:"previousId"`
+	UserId     string `json:"userId"`
+	Message
+}
+
+// Client which batches messages and flushes at the given Interval or
+// when the Size limit is exceeded. Set Verbose to true to enable
+// logging output.
+type Client struct {
+	Endpoint string
+	// Interval represents the duration at which messages are flushed. It may be
+	// configured only before any messages are enqueued.
+	Interval time.Duration
+	Size     int
+	Logger   *log.Logger
+	Verbose  bool
+	Client   http.Client
+	key      string
+	msgs     chan interface{}
+	quit     chan struct{}
+	shutdown chan struct{}
+	uid      func() string
+	now      func() time.Time
+	once     sync.Once
+	wg       sync.WaitGroup
+
+	// These synchronization primitives are used to control how many goroutines
+	// are spawned by the client for uploads.
+	upmtx   sync.Mutex
+	upcond  sync.Cond
+	upcount int
+}
+
+// New client with write key.
+func New(key string) *Client {
+	c := &Client{
+		Endpoint: Endpoint,
+		Interval: 5 * time.Second,
+		Size:     250,
+		Logger:   log.New(os.Stderr, "segment ", log.LstdFlags),
+		Verbose:  false,
+		Client:   *http.DefaultClient,
+		key:      key,
+		msgs:     make(chan interface{}, 100),
+		quit:     make(chan struct{}),
+		shutdown: make(chan struct{}),
+		now:      time.Now,
+		uid:      uid,
+	}
+
+	c.upcond.L = &c.upmtx
+	return c
+}
+
+// Alias buffers an "alias" message.
+func (c *Client) Alias(msg *Alias) error {
+	if msg.UserId == "" {
+		return errors.New("You must pass a 'userId'.")
+	}
+
+	if msg.PreviousId == "" {
+		return errors.New("You must pass a 'previousId'.")
+	}
+
+	msg.Type = "alias"
+	c.queue(msg)
+
+	return nil
+}
+
+// Page buffers an "page" message.
+func (c *Client) Page(msg *Page) error {
+	if msg.UserId == "" && msg.AnonymousId == "" {
+		return errors.New("You must pass either an 'anonymousId' or 'userId'.")
+	}
+
+	msg.Type = "page"
+	c.queue(msg)
+
+	return nil
+}
+
+// Group buffers an "group" message.
+func (c *Client) Group(msg *Group) error {
+	if msg.GroupId == "" {
+		return errors.New("You must pass a 'groupId'.")
+	}
+
+	if msg.UserId == "" && msg.AnonymousId == "" {
+		return errors.New("You must pass either an 'anonymousId' or 'userId'.")
+	}
+
+	msg.Type = "group"
+	c.queue(msg)
+
+	return nil
+}
+
+// Identify buffers an "identify" message.
+func (c *Client) Identify(msg *Identify) error {
+	if msg.UserId == "" && msg.AnonymousId == "" {
+		return errors.New("You must pass either an 'anonymousId' or 'userId'.")
+	}
+
+	msg.Type = "identify"
+	c.queue(msg)
+
+	return nil
+}
+
+// Track buffers an "track" message.
+func (c *Client) Track(msg *Track) error {
+	if msg.Event == "" {
+		return errors.New("You must pass 'event'.")
+	}
+
+	if msg.UserId == "" && msg.AnonymousId == "" {
+		return errors.New("You must pass either an 'anonymousId' or 'userId'.")
+	}
+
+	msg.Type = "track"
+	c.queue(msg)
+
+	return nil
+}
+
+func (c *Client) startLoop() {
+	go c.loop()
+}
+
+// Queue message.
+func (c *Client) queue(msg message) {
+	c.once.Do(c.startLoop)
+	msg.setMessageId(c.uid())
+	msg.setTimestamp(timestamp(c.now()))
+	c.msgs <- msg
+}
+
+// Close and flush metrics.
+func (c *Client) Close() error {
+	c.once.Do(c.startLoop)
+	c.quit <- struct{}{}
+	close(c.msgs)
+	<-c.shutdown
+	return nil
+}
+
+func (c *Client) sendAsync(msgs []interface{}) {
+	c.upmtx.Lock()
+	for c.upcount == 1000 {
+		c.upcond.Wait()
+	}
+	c.upcount++
+	c.upmtx.Unlock()
+	c.wg.Add(1)
+	go func() {
+		err := c.send(msgs)
+		if err != nil {
+			c.logf(err.Error())
+		}
+		c.upmtx.Lock()
+		c.upcount--
+		c.upcond.Signal()
+		c.upmtx.Unlock()
+		c.wg.Done()
+	}()
+}
+
+// Send batch request.
+func (c *Client) send(msgs []interface{}) error {
+	if len(msgs) == 0 {
+		return nil
+	}
+
+	batch := new(Batch)
+	batch.Messages = msgs
+	batch.MessageId = c.uid()
+	batch.SentAt = timestamp(c.now())
+	batch.Context = DefaultContext
+
+	b, err := json.Marshal(batch)
+	if err != nil {
+		return fmt.Errorf("error marshalling msgs: %s", err)
+	}
+
+	for i := 0; i < 10; i++ {
+		if err = c.upload(b); err == nil {
+			return nil
+		}
+		Backo.Sleep(i)
+	}
+
+	return err
+}
+
+// Upload serialized batch message.
+func (c *Client) upload(b []byte) error {
+	url := c.Endpoint + "/v1/batch"
+	req, err := http.NewRequest("POST", url, bytes.NewReader(b))
+	if err != nil {
+		return fmt.Errorf("error creating request: %s", err)
+	}
+
+	req.Header.Add("User-Agent", "analytics-go (version: "+Version+")")
+	req.Header.Add("Content-Type", "application/json")
+	req.Header.Add("Content-Length", string(len(b)))
+	req.SetBasicAuth(c.key, "")
+
+	res, err := c.Client.Do(req)
+	if err != nil {
+		return fmt.Errorf("error sending request: %s", err)
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode < 400 {
+		c.verbose("response %s", res.Status)
+		return nil
+	}
+
+	body, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return fmt.Errorf("error reading response body: %s", err)
+	}
+
+	return fmt.Errorf("response %s: %d – %s", res.Status, res.StatusCode, string(body))
+}
+
+// Batch loop.
+func (c *Client) loop() {
+	var msgs []interface{}
+	tick := time.NewTicker(c.Interval)
+
+	for {
+		select {
+		case msg := <-c.msgs:
+			c.verbose("buffer (%d/%d) %v", len(msgs), c.Size, msg)
+			msgs = append(msgs, msg)
+			if len(msgs) == c.Size {
+				c.verbose("exceeded %d messages – flushing", c.Size)
+				c.sendAsync(msgs)
+				msgs = make([]interface{}, 0, c.Size)
+			}
+		case <-tick.C:
+			if len(msgs) > 0 {
+				c.verbose("interval reached - flushing %d", len(msgs))
+				c.sendAsync(msgs)
+				msgs = make([]interface{}, 0, c.Size)
+			} else {
+				c.verbose("interval reached – nothing to send")
+			}
+		case <-c.quit:
+			tick.Stop()
+			c.verbose("exit requested – draining msgs")
+			// drain the msg channel.
+			for msg := range c.msgs {
+				c.verbose("buffer (%d/%d) %v", len(msgs), c.Size, msg)
+				msgs = append(msgs, msg)
+			}
+			c.verbose("exit requested – flushing %d", len(msgs))
+			c.sendAsync(msgs)
+			c.wg.Wait()
+			c.verbose("exit")
+			c.shutdown <- struct{}{}
+			return
+		}
+	}
+}
+
+// Verbose log.
+func (c *Client) verbose(msg string, args ...interface{}) {
+	if c.Verbose {
+		c.Logger.Printf(msg, args...)
+	}
+}
+
+// Unconditional log.
+func (c *Client) logf(msg string, args ...interface{}) {
+	c.Logger.Printf(msg, args...)
+}
+
+// Set message timestamp if one is not already set.
+func (m *Message) setTimestamp(s string) {
+	if m.Timestamp == "" {
+		m.Timestamp = s
+	}
+}
+
+// Set message id.
+func (m *Message) setMessageId(s string) {
+	if m.MessageId == "" {
+		m.MessageId = s
+	}
+}
+
+// Return formatted timestamp.
+func timestamp(t time.Time) string {
+	return strftime.Format("%Y-%m-%dT%H:%M:%S%z", t)
+}
+
+// Return uuid string.
+func uid() string {
+	return uuid.NewRandom().String()
+}
diff --git a/vendor/github.com/segmentio/analytics-go/analytics_test.go b/vendor/github.com/segmentio/analytics-go/analytics_test.go
new file mode 100644
index 000000000..c6f0dc4f2
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/analytics_test.go
@@ -0,0 +1,478 @@
+package analytics
+
+import "net/http/httptest"
+import "encoding/json"
+import "net/http"
+import "testing"
+import "bytes"
+import "time"
+import "fmt"
+import "io"
+
+func mockId() string { return "I'm unique" }
+
+func mockTime() time.Time {
+	// time.Unix(0, 0) fails on Circle
+	return time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC)
+}
+
+func mockServer() (chan []byte, *httptest.Server) {
+	done := make(chan []byte, 1)
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		buf := bytes.NewBuffer(nil)
+		io.Copy(buf, r.Body)
+
+		var v interface{}
+		err := json.Unmarshal(buf.Bytes(), &v)
+		if err != nil {
+			panic(err)
+		}
+
+		b, err := json.MarshalIndent(v, "", "  ")
+		if err != nil {
+			panic(err)
+		}
+
+		done <- b
+	}))
+
+	return done, server
+}
+
+func ExampleTrack() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 1
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+	})
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleClose() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+	})
+
+	client.Close()
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleInterval() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+	})
+
+	// Will flush in 5 seconds (default interval).
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleTrackWithTimestampSet() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 1
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+		Message: Message{
+			Timestamp: timestamp(time.Date(2015, time.July, 10, 23, 0, 0, 0, time.UTC)),
+		},
+	})
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2015-07-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleTrackWithMessageIdSet() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 1
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+		Message: Message{
+			MessageId: "abc",
+		},
+	})
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "abc",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleTrack_context() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 1
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+		Context: map[string]interface{}{
+			"whatever": "here",
+		},
+	})
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "context": {
+	//         "whatever": "here"
+	//       },
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleTrack_many() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 3
+
+	for i := 0; i < 5; i++ {
+		client.Track(&Track{
+			Event:  "Download",
+			UserId: "123456",
+			Properties: map[string]interface{}{
+				"application": "Segment Desktop",
+				"version":     i,
+			},
+		})
+	}
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "version": 0
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     },
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "version": 1
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     },
+	//     {
+	//       "event": "Download",
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "version": 2
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+func ExampleTrackWithIntegrations() {
+	body, server := mockServer()
+	defer server.Close()
+
+	client := New("h97jamjwbh")
+	client.Endpoint = server.URL
+	client.now = mockTime
+	client.uid = mockId
+	client.Size = 1
+
+	client.Track(&Track{
+		Event:  "Download",
+		UserId: "123456",
+		Properties: map[string]interface{}{
+			"application": "Segment Desktop",
+			"version":     "1.1.0",
+			"platform":    "osx",
+		},
+		Integrations: map[string]interface{}{
+			"All":      true,
+			"Intercom": false,
+			"Mixpanel": true,
+		},
+	})
+
+	fmt.Printf("%s\n", <-body)
+	// Output:
+	// {
+	//   "batch": [
+	//     {
+	//       "event": "Download",
+	//       "integrations": {
+	//         "All": true,
+	//         "Intercom": false,
+	//         "Mixpanel": true
+	//       },
+	//       "messageId": "I'm unique",
+	//       "properties": {
+	//         "application": "Segment Desktop",
+	//         "platform": "osx",
+	//         "version": "1.1.0"
+	//       },
+	//       "timestamp": "2009-11-10T23:00:00+0000",
+	//       "type": "track",
+	//       "userId": "123456"
+	//     }
+	//   ],
+	//   "context": {
+	//     "library": {
+	//       "name": "analytics-go",
+	//       "version": "2.1.0"
+	//     }
+	//   },
+	//   "messageId": "I'm unique",
+	//   "sentAt": "2009-11-10T23:00:00+0000"
+	// }
+}
+
+// Tests that calling Close right after creating the client object doesn't
+// block.
+// Bug: https://github.com/segmentio/analytics-go/issues/43
+func TestCloseFinish(_ *testing.T) {
+	c := New("test")
+	c.Close()
+}
diff --git a/vendor/github.com/segmentio/analytics-go/circle.yml b/vendor/github.com/segmentio/analytics-go/circle.yml
new file mode 100644
index 000000000..11733e196
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/circle.yml
@@ -0,0 +1,18 @@
+machine:
+  environment:
+    IMPORT_PATH: "github.com/$CIRCLE_PROJECT_USERNAME/$CIRCLE_PROJECT_REPONAME"
+
+dependencies:
+  pre:
+    - go get github.com/tools/godep
+
+  override:
+    - mkdir -p "$GOPATH/src/$IMPORT_PATH"
+    - rsync -azC --delete ./ "$GOPATH/src/$IMPORT_PATH/"
+
+test:
+  pre:
+    - make vet
+
+  override:
+    - make test
diff --git a/vendor/github.com/segmentio/analytics-go/cli/cli.go b/vendor/github.com/segmentio/analytics-go/cli/cli.go
new file mode 100644
index 000000000..9d1f940c9
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/cli/cli.go
@@ -0,0 +1,174 @@
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"os"
+	"reflect"
+
+	"github.com/segmentio/analytics-go"
+	"github.com/tj/docopt"
+)
+
+const Usage = `
+Analytics Go CLI
+
+Usage:
+  analytics track <event> [--properties=<properties>] [--context=<context>] [--writeKey=<writeKey>] [--userId=<userId>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics screen <name> [--properties=<properties>] [--context=<context>] [--writeKey=<writeKey>] [--userId=<userId>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics page <name> [--properties=<properties>] [--context=<context>] [--writeKey=<writeKey>] [--userId=<userId>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics identify [--traits=<traits>] [--context=<context>] [--writeKey=<writeKey>] [--userId=<userId>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics group --groupId=<groupId> [--traits=<traits>] [--properties=<properties>] [--context=<context>] [--writeKey=<writeKey>] [--userId=<userId>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics alias --userId=<userId> --previousId=<previousId> [--traits=<traits>] [--properties=<properties>] [--context=<context>] [--writeKey=<writeKey>] [--anonymousId=<anonymousId>] [--integrations=<integrations>] [--timestamp=<timestamp>]
+  analytics -h | --help
+  analytics --version
+
+Options:
+  -h --help     Show this screen.
+  --version     Show version.
+`
+
+func main() {
+	arguments, err := docopt.Parse(Usage, nil, true, "Anaytics Go CLI", false)
+	check(err)
+
+	writeKey := getOptionalString(arguments, "--writeKey")
+	if writeKey == "" {
+		writeKey = os.Getenv("SEGMENT_WRITE_KEY")
+		if writeKey == "" {
+			log.Fatal("either $SEGMENT_WRITE_KEY or --writeKey must be provided")
+		}
+	}
+
+	client := analytics.New(writeKey)
+	client.Size = 1
+	client.Verbose = true
+
+	if arguments["track"].(bool) {
+		m := &analytics.Track{
+			Event: arguments["<event>"].(string),
+		}
+		properties := getOptionalString(arguments, "--properties")
+		if properties != "" {
+			var parsedProperties map[string]interface{}
+			err := json.Unmarshal([]byte(properties), &parsedProperties)
+			check(err)
+			m.Properties = parsedProperties
+		}
+
+		setCommonFields(m, arguments)
+
+		check(client.Track(m))
+	}
+
+	if arguments["screen"].(bool) || arguments["page"].(bool) {
+		m := &analytics.Page{
+			Name: arguments["<name>"].(string),
+		}
+		/* Bug in Go library - page has traits not properties.
+		properties := getOptionalString(arguments, "--properties")
+		if properties != "" {
+			var parsedProperties map[string]interface{}
+			err := json.Unmarshal([]byte(properties), &parsedProperties)
+			check(err)
+			t.Properties = parsedProperties
+		}
+		*/
+
+		setCommonFields(m, arguments)
+
+		check(client.Page(m))
+	}
+
+	if arguments["identify"].(bool) {
+		m := &analytics.Identify{}
+		traits := getOptionalString(arguments, "--traits")
+		if traits != "" {
+			var parsedTraits map[string]interface{}
+			err := json.Unmarshal([]byte(traits), &parsedTraits)
+			check(err)
+			m.Traits = parsedTraits
+		}
+
+		setCommonFields(m, arguments)
+
+		check(client.Identify(m))
+	}
+
+	if arguments["group"].(bool) {
+		m := &analytics.Group{
+			GroupId: arguments["--groupId"].(string),
+		}
+		traits := getOptionalString(arguments, "--traits")
+		if traits != "" {
+			var parsedTraits map[string]interface{}
+			err := json.Unmarshal([]byte(traits), &parsedTraits)
+			check(err)
+			m.Traits = parsedTraits
+		}
+
+		setCommonFields(m, arguments)
+
+		check(client.Group(m))
+	}
+
+	if arguments["alias"].(bool) {
+		m := &analytics.Alias{
+			PreviousId: arguments["--previousId"].(string),
+		}
+
+		setCommonFields(m, arguments)
+
+		check(client.Alias(m))
+	}
+
+	client.Close()
+}
+
+func setCommonFields(message interface{}, arguments map[string]interface{}) {
+	userId := getOptionalString(arguments, "--userId")
+	if userId != "" {
+		setFieldValue(message, "UserId", userId)
+	}
+	anonymousId := getOptionalString(arguments, "--anonymousId")
+	if anonymousId != "" {
+		setFieldValue(message, "AnonymousId", anonymousId)
+	}
+	integrations := getOptionalString(arguments, "--integrations")
+	if integrations != "" {
+		var parsedIntegrations map[string]interface{}
+		err := json.Unmarshal([]byte(integrations), &parsedIntegrations)
+		check(err)
+		setFieldValue(message, "Integrations", parsedIntegrations)
+	}
+	context := getOptionalString(arguments, "--context")
+	if context != "" {
+		var parsedContext map[string]interface{}
+		err := json.Unmarshal([]byte(context), &parsedContext)
+		check(err)
+		setFieldValue(message, "Context", parsedContext)
+
+	}
+	timestamp := getOptionalString(arguments, "--timestamp")
+	if timestamp != "" {
+		setFieldValue(message, "Timestamp", timestamp)
+	}
+}
+
+func setFieldValue(target interface{}, field string, value interface{}) {
+	reflect.ValueOf(target).Elem().FieldByName(field).Set(reflect.ValueOf(value))
+}
+
+func getOptionalString(m map[string]interface{}, k string) string {
+	v := m[k]
+	if v == nil {
+		return ""
+	}
+	return v.(string)
+}
+
+func check(err error) {
+	if err != nil {
+		log.Fatal(err)
+	}
+}
diff --git a/vendor/github.com/segmentio/analytics-go/examples/track.go b/vendor/github.com/segmentio/analytics-go/examples/track.go
new file mode 100644
index 000000000..484c38efa
--- /dev/null
+++ b/vendor/github.com/segmentio/analytics-go/examples/track.go
@@ -0,0 +1,36 @@
+package main
+
+import "github.com/segmentio/analytics-go"
+import "time"
+
+func main() {
+	client := analytics.New("h97jamjwbh")
+	client.Interval = 30 * time.Second
+	client.Size = 100
+	client.Verbose = true
+
+	done := time.After(3 * time.Second)
+	tick := time.Tick(50 * time.Millisecond)
+
+out:
+	for {
+		select {
+		case <-done:
+			println("exiting")
+			break out
+		case <-tick:
+			client.Track(&analytics.Track{
+				Event:  "Download",
+				UserId: "123456",
+				Properties: map[string]interface{}{
+					"application": "Segment Desktop",
+					"version":     "1.1.0",
+					"platform":    "osx",
+				},
+			})
+		}
+	}
+
+	println("flushing")
+	client.Close()
+}
diff --git a/vendor/github.com/segmentio/backo-go/README.md b/vendor/github.com/segmentio/backo-go/README.md
new file mode 100644
index 000000000..1362becf1
--- /dev/null
+++ b/vendor/github.com/segmentio/backo-go/README.md
@@ -0,0 +1,80 @@
+Backo [![GoDoc](http://godoc.org/github.com/segmentio/backo-go?status.png)](http://godoc.org/github.com/segmentio/backo-go)
+-----
+
+Exponential backoff for Go (Go port of segmentio/backo).
+
+
+Usage
+-----
+
+```go
+import "github.com/segmentio/backo-go"
+
+// Create a Backo instance.
+backo := backo.NewBacko(milliseconds(100), 2, 1, milliseconds(10*1000))
+// OR with defaults.
+backo := backo.DefaultBacko()
+
+// Use the ticker API.
+ticker := b.NewTicker()
+for {
+    timeout := time.After(5 * time.Minute)
+    select {
+    case  <-ticker.C:
+        fmt.Println("ticked")
+    case <- timeout:
+        fmt.Println("timed out")
+    }
+}
+
+// Or simply work with backoff intervals directly.
+for i := 0; i < n; i++ {
+    // Sleep the current goroutine.
+    backo.Sleep(i)
+    // Retrieve the duration manually.
+    duration := backo.Duration(i)
+}
+```
+
+License
+-------
+
+```
+WWWWWW||WWWWWW
+ W W W||W W W
+      ||
+    ( OO )__________
+     /  |           \
+    /o o|    MIT     \
+    \___/||_||__||_|| *
+         || ||  || ||
+        _||_|| _||_||
+       (__|__|(__|__|
+
+The MIT License (MIT)
+
+Copyright (c) 2015 Segment, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+```
+
+
+
+ [1]: http://github.com/segmentio/backo-java
+ [2]: http://repository.sonatype.org/service/local/artifact/maven/redirect?r=central-proxy&g=com.segment.backo&a=backo&v=LATEST
\ No newline at end of file
diff --git a/vendor/github.com/segmentio/backo-go/backo.go b/vendor/github.com/segmentio/backo-go/backo.go
new file mode 100644
index 000000000..6f7b6d5e2
--- /dev/null
+++ b/vendor/github.com/segmentio/backo-go/backo.go
@@ -0,0 +1,83 @@
+package backo
+
+import (
+	"math"
+	"math/rand"
+	"time"
+)
+
+type Backo struct {
+	base   time.Duration
+	factor uint8
+	jitter float64
+	cap    time.Duration
+}
+
+// Creates a backo instance with the given parameters
+func NewBacko(base time.Duration, factor uint8, jitter float64, cap time.Duration) *Backo {
+	return &Backo{base, factor, jitter, cap}
+}
+
+// Creates a backo instance with the following defaults:
+//   base: 100 milliseconds
+//   factor: 2
+//   jitter: 0
+//   cap: 10 seconds
+func DefaultBacko() *Backo {
+	return NewBacko(time.Millisecond*100, 2, 0, time.Second*10)
+}
+
+// Duration returns the backoff interval for the given attempt.
+func (backo *Backo) Duration(attempt int) time.Duration {
+	duration := float64(backo.base) * math.Pow(float64(backo.factor), float64(attempt))
+
+	if backo.jitter != 0 {
+		random := rand.Float64()
+		deviation := math.Floor(random * backo.jitter * duration)
+		if (int(math.Floor(random*10)) & 1) == 0 {
+			duration = duration - deviation
+		} else {
+			duration = duration + deviation
+		}
+	}
+
+	duration = math.Min(float64(duration), float64(backo.cap))
+	return time.Duration(duration)
+}
+
+// Sleep pauses the current goroutine for the backoff interval for the given attempt.
+func (backo *Backo) Sleep(attempt int) {
+	duration := backo.Duration(attempt)
+	time.Sleep(duration)
+}
+
+type Ticker struct {
+	done chan struct{}
+	C    <-chan time.Time
+}
+
+func (b *Backo) NewTicker() *Ticker {
+	c := make(chan time.Time, 1)
+	ticker := &Ticker{
+		done: make(chan struct{}, 1),
+		C:    c,
+	}
+
+	go func() {
+		for i := 0; ; i++ {
+			select {
+			case t := <-time.After(b.Duration(i)):
+				c <- t
+			case <-ticker.done:
+				close(c)
+				return
+			}
+		}
+	}()
+
+	return ticker
+}
+
+func (t *Ticker) Stop() {
+	t.done <- struct{}{}
+}
diff --git a/vendor/github.com/segmentio/backo-go/backo_test.go b/vendor/github.com/segmentio/backo-go/backo_test.go
new file mode 100644
index 000000000..89933acf7
--- /dev/null
+++ b/vendor/github.com/segmentio/backo-go/backo_test.go
@@ -0,0 +1,77 @@
+package backo
+
+import (
+	"fmt"
+	"math"
+	"testing"
+	"time"
+
+	"github.com/bmizerany/assert"
+)
+
+// Tests default backo behaviour.
+func TestDefaults(t *testing.T) {
+	backo := DefaultBacko()
+
+	assert.Equal(t, milliseconds(100), backo.Duration(0))
+	assert.Equal(t, milliseconds(200), backo.Duration(1))
+	assert.Equal(t, milliseconds(400), backo.Duration(2))
+	assert.Equal(t, milliseconds(800), backo.Duration(3))
+}
+
+// Tests backo does not exceed cap.
+func TestCap(t *testing.T) {
+	backo := NewBacko(milliseconds(100), 2, 0, milliseconds(600))
+
+	assert.Equal(t, milliseconds(100), backo.Duration(0))
+	assert.Equal(t, milliseconds(200), backo.Duration(1))
+	assert.Equal(t, milliseconds(400), backo.Duration(2))
+	assert.Equal(t, milliseconds(600), backo.Duration(3))
+}
+
+// Tests that jitter adds randomness.
+func TestJitter(t *testing.T) {
+	defaultBacko := NewBacko(milliseconds(100), 2, 1, milliseconds(10*1000))
+	jitterBacko := NewBacko(milliseconds(100), 2, 1, milliseconds(10*1000))
+
+	// TODO: Check jittered durations are within a range.
+	assert.NotEqual(t, jitterBacko.Duration(0), defaultBacko.Duration(0))
+	assert.NotEqual(t, jitterBacko.Duration(1), defaultBacko.Duration(1))
+	assert.NotEqual(t, jitterBacko.Duration(2), defaultBacko.Duration(2))
+	assert.NotEqual(t, jitterBacko.Duration(3), defaultBacko.Duration(3))
+}
+
+func ExampleBacko_BackoffDefault() {
+	b := DefaultBacko()
+	ticker := b.NewTicker()
+
+	for i := 0; i < 6; i++ {
+		start := time.Now()
+		select {
+		case t := <-ticker.C:
+			fmt.Println(nearest10Millis(t.Sub(start)))
+		}
+	}
+
+	ticker.Stop()
+
+	// Output:
+	// 100
+	// 200
+	// 400
+	// 800
+	// 1600
+	// 3200
+}
+
+func nearest10Millis(d time.Duration) float64 {
+	// Typically d is something like 11 or 21, so do some magic to round the
+	// durations to the nearest 10. We divide d by 10, floor it, and multiply it
+	// by 10 again.
+	return math.Floor(float64(d/time.Millisecond/10) * 10)
+}
+
+// Returns the given milliseconds as time.Duration
+func milliseconds(ms int64) time.Duration {
+	return time.Duration(ms * 1000 * 1000)
+}
diff --git a/vendor/github.com/xtgo/uuid/AUTHORS b/vendor/github.com/xtgo/uuid/AUTHORS
new file mode 100644
index 000000000..a6f045160
--- /dev/null
+++ b/vendor/github.com/xtgo/uuid/AUTHORS
@@ -0,0 +1,5 @@
+# This source file refers to The gocql Authors for copyright purposes.
+
+Christoph Hack <christoph@tux21b.org>
+Jonathan Rudenberg <jonathan@titanous.com>
+Thorsten von Eicken <tve@rightscale.com>
diff --git a/vendor/github.com/xtgo/uuid/LICENSE b/vendor/github.com/xtgo/uuid/LICENSE
new file mode 100644
index 000000000..18d25f923
--- /dev/null
+++ b/vendor/github.com/xtgo/uuid/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2012 The gocql Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/xtgo/uuid/uuid.go b/vendor/github.com/xtgo/uuid/uuid.go
new file mode 100644
index 000000000..a0fd7a5a5
--- /dev/null
+++ b/vendor/github.com/xtgo/uuid/uuid.go
@@ -0,0 +1,204 @@
+// Copyright (c) 2012 The gocql Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package uuid can be used to generate and parse universally unique
+// identifiers, a standardized format in the form of a 128 bit number.
+//
+// http://tools.ietf.org/html/rfc4122
+package uuid
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"errors"
+	"io"
+	"net"
+	"strconv"
+	"time"
+)
+
+type UUID [16]byte
+
+var hardwareAddr []byte
+
+const (
+	VariantNCSCompat = 0
+	VariantIETF      = 2
+	VariantMicrosoft = 6
+	VariantFuture    = 7
+)
+
+func init() {
+	if interfaces, err := net.Interfaces(); err == nil {
+		for _, i := range interfaces {
+			if i.Flags&net.FlagLoopback == 0 && len(i.HardwareAddr) > 0 {
+				hardwareAddr = i.HardwareAddr
+				break
+			}
+		}
+	}
+	if hardwareAddr == nil {
+		// If we failed to obtain the MAC address of the current computer,
+		// we will use a randomly generated 6 byte sequence instead and set
+		// the multicast bit as recommended in RFC 4122.
+		hardwareAddr = make([]byte, 6)
+		_, err := io.ReadFull(rand.Reader, hardwareAddr)
+		if err != nil {
+			panic(err)
+		}
+		hardwareAddr[0] = hardwareAddr[0] | 0x01
+	}
+}
+
+// Parse parses a 32 digit hexadecimal number (that might contain hyphens)
+// representing an UUID.
+func Parse(input string) (UUID, error) {
+	var u UUID
+	j := 0
+	for i := 0; i < len(input); i++ {
+		b := input[i]
+		switch {
+		default:
+			fallthrough
+		case j == 32:
+			goto err
+		case b == '-':
+			continue
+		case '0' <= b && b <= '9':
+			b -= '0'
+		case 'a' <= b && b <= 'f':
+			b -= 'a' - 10
+		case 'A' <= b && b <= 'F':
+			b -= 'A' - 10
+		}
+		u[j/2] |= b << byte(^j&1<<2)
+		j++
+	}
+	if j == 32 {
+		return u, nil
+	}
+err:
+	return UUID{}, errors.New("invalid UUID " + strconv.Quote(input))
+}
+
+// FromBytes converts a raw byte slice to an UUID. It will panic if the slice
+// isn't exactly 16 bytes long.
+func FromBytes(input []byte) UUID {
+	var u UUID
+	if len(input) != 16 {
+		panic("UUIDs must be exactly 16 bytes long")
+	}
+	copy(u[:], input)
+	return u
+}
+
+// NewRandom generates a totally random UUID (version 4) as described in
+// RFC 4122.
+func NewRandom() UUID {
+	var u UUID
+	io.ReadFull(rand.Reader, u[:])
+	u[6] &= 0x0F // clear version
+	u[6] |= 0x40 // set version to 4 (random uuid)
+	u[8] &= 0x3F // clear variant
+	u[8] |= 0x80 // set to IETF variant
+	return u
+}
+
+var timeBase = time.Date(1582, time.October, 15, 0, 0, 0, 0, time.UTC).Unix()
+
+// NewTime generates a new time based UUID (version 1) as described in RFC
+// 4122. This UUID contains the MAC address of the node that generated the
+// UUID, a timestamp and a sequence number.
+func NewTime() UUID {
+	var u UUID
+
+	now := time.Now().In(time.UTC)
+	t := uint64(now.Unix()-timeBase)*10000000 + uint64(now.Nanosecond()/100)
+	u[0], u[1], u[2], u[3] = byte(t>>24), byte(t>>16), byte(t>>8), byte(t)
+	u[4], u[5] = byte(t>>40), byte(t>>32)
+	u[6], u[7] = byte(t>>56)&0x0F, byte(t>>48)
+
+	var clockSeq [2]byte
+	io.ReadFull(rand.Reader, clockSeq[:])
+	u[8] = clockSeq[1]
+	u[9] = clockSeq[0]
+
+	copy(u[10:], hardwareAddr)
+
+	u[6] |= 0x10 // set version to 1 (time based uuid)
+	u[8] &= 0x3F // clear variant
+	u[8] |= 0x80 // set to IETF variant
+
+	return u
+}
+
+// String returns the UUID in it's canonical form, a 32 digit hexadecimal
+// number in the form of xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
+func (u UUID) String() string {
+	buf := [36]byte{8: '-', 13: '-', 18: '-', 23: '-'}
+	hex.Encode(buf[0:], u[0:4])
+	hex.Encode(buf[9:], u[4:6])
+	hex.Encode(buf[14:], u[6:8])
+	hex.Encode(buf[19:], u[8:10])
+	hex.Encode(buf[24:], u[10:])
+	return string(buf[:])
+}
+
+// Bytes returns the raw byte slice for this UUID. A UUID is always 128 bits
+// (16 bytes) long.
+func (u UUID) Bytes() []byte {
+	return u[:]
+}
+
+// Variant returns the variant of this UUID. This package will only generate
+// UUIDs in the IETF variant.
+func (u UUID) Variant() int {
+	x := u[8]
+	switch byte(0) {
+	case x & 0x80:
+		return VariantNCSCompat
+	case x & 0x40:
+		return VariantIETF
+	case x & 0x20:
+		return VariantMicrosoft
+	}
+	return VariantFuture
+}
+
+// Version extracts the version of this UUID variant. The RFC 4122 describes
+// five kinds of UUIDs.
+func (u UUID) Version() int {
+	return int(u[6] & 0xF0 >> 4)
+}
+
+// Node extracts the MAC address of the node who generated this UUID. It will
+// return nil if the UUID is not a time based UUID (version 1).
+func (u UUID) Node() []byte {
+	if u.Version() != 1 {
+		return nil
+	}
+	return u[10:]
+}
+
+// Timestamp extracts the timestamp information from a time based UUID
+// (version 1).
+func (u UUID) Timestamp() uint64 {
+	if u.Version() != 1 {
+		return 0
+	}
+	return uint64(u[0])<<24 + uint64(u[1])<<16 + uint64(u[2])<<8 +
+		uint64(u[3]) + uint64(u[4])<<40 + uint64(u[5])<<32 +
+		uint64(u[7])<<48 + uint64(u[6]&0x0F)<<56
+}
+
+// Time is like Timestamp, except that it returns a time.Time.
+func (u UUID) Time() time.Time {
+	t := u.Timestamp()
+	if t == 0 {
+		return time.Time{}
+	}
+	sec := t / 10000000
+	nsec := t - sec
+	return time.Unix(int64(sec)+timeBase, int64(nsec))
+}
diff --git a/vendor/github.com/xtgo/uuid/uuid_test.go b/vendor/github.com/xtgo/uuid/uuid_test.go
new file mode 100644
index 000000000..3cef4a31a
--- /dev/null
+++ b/vendor/github.com/xtgo/uuid/uuid_test.go
@@ -0,0 +1,102 @@
+// Copyright (c) 2012 The gocql Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package uuid
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestNil(t *testing.T) {
+	var uuid UUID
+	want, got := "00000000-0000-0000-0000-000000000000", uuid.String()
+	if want != got {
+		t.Fatalf("TestNil: expected %q got %q", want, got)
+	}
+}
+
+var tests = []struct {
+	input   string
+	variant int
+	version int
+}{
+	{"b4f00409-cef8-4822-802c-deb20704c365", VariantIETF, 4},
+	{"f81d4fae-7dec-11d0-a765-00a0c91e6bf6", VariantIETF, 1},
+	{"00000000-7dec-11d0-a765-00a0c91e6bf6", VariantIETF, 1},
+	{"3051a8d7-aea7-1801-e0bf-bc539dd60cf3", VariantFuture, 1},
+	{"3051a8d7-aea7-2801-e0bf-bc539dd60cf3", VariantFuture, 2},
+	{"3051a8d7-aea7-3801-e0bf-bc539dd60cf3", VariantFuture, 3},
+	{"3051a8d7-aea7-4801-e0bf-bc539dd60cf3", VariantFuture, 4},
+	{"3051a8d7-aea7-3801-e0bf-bc539dd60cf3", VariantFuture, 5},
+	{"d0e817e1-e4b1-1801-3fe6-b4b60ccecf9d", VariantNCSCompat, 0},
+	{"d0e817e1-e4b1-1801-bfe6-b4b60ccecf9d", VariantIETF, 1},
+	{"d0e817e1-e4b1-1801-dfe6-b4b60ccecf9d", VariantMicrosoft, 0},
+	{"d0e817e1-e4b1-1801-ffe6-b4b60ccecf9d", VariantFuture, 0},
+}
+
+func TestPredefined(t *testing.T) {
+	for i := range tests {
+		uuid, err := Parse(tests[i].input)
+		if err != nil {
+			t.Errorf("Parse #%d: %v", i, err)
+			continue
+		}
+
+		if str := uuid.String(); str != tests[i].input {
+			t.Errorf("String #%d: expected %q got %q", i, tests[i].input, str)
+			continue
+		}
+
+		if variant := uuid.Variant(); variant != tests[i].variant {
+			t.Errorf("Variant #%d: expected %d got %d", i, tests[i].variant, variant)
+		}
+
+		if tests[i].variant == VariantIETF {
+			if version := uuid.Version(); version != tests[i].version {
+				t.Errorf("Version #%d: expected %d got %d", i, tests[i].version, version)
+			}
+		}
+	}
+}
+
+func TestNewRandom(t *testing.T) {
+	for i := 0; i < 20; i++ {
+		uuid := NewRandom()
+
+		if variant := uuid.Variant(); variant != VariantIETF {
+			t.Errorf("wrong variant. expected %d got %d", VariantIETF, variant)
+		}
+		if version := uuid.Version(); version != 4 {
+			t.Errorf("wrong version. expected %d got %d", 4, version)
+		}
+	}
+}
+
+func TestNewTime(t *testing.T) {
+	var node []byte
+	timestamp := uint64(0)
+	for i := 0; i < 20; i++ {
+		uuid := NewTime()
+
+		if variant := uuid.Variant(); variant != VariantIETF {
+			t.Errorf("wrong variant. expected %d got %d", VariantIETF, variant)
+		}
+		if version := uuid.Version(); version != 1 {
+			t.Errorf("wrong version. expected %d got %d", 1, version)
+		}
+
+		if n := uuid.Node(); !bytes.Equal(n, node) && i > 0 {
+			t.Errorf("wrong node. expected %x, got %x", node, n)
+		} else if i == 0 {
+			node = n
+		}
+
+		ts := uuid.Timestamp()
+		if ts < timestamp {
+			t.Errorf("timestamps must grow")
+		}
+		timestamp = ts
+	}
+}